Examine source code of Chess.com limit

{
  "manifest_version": 2,
  "name": "Chess.com daily games limit",
  "version": "1.2",
  "description": "Limits the number of daily games at chess.com to avoid tilt or addiction. Set your daily limit in the popup window and enjoy the game!",
  "icons": {
    "48": "icons/chess.png"
  },
  "permissions": [
    "activeTab",
    "storage"
  ],
  "browser_action": {
    "default_popup": "popups/chess_popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.chess.com/*"
      ],
      "js": [
        "chess_limit.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{064814a9-d96e-4b2a-ac8a-9b9416b678e6}"
    }
  }
}